SEA-FISHERIES LABORATORY. 163 



the addition of faecal matter ; that the faecal matter 

 obtained from cases of typhoid was more inimical than 

 that obtained from healthy subjects ; and that there was 

 considerable toleration to peptonised broth. 



V. The infection of the oyster by the micro-organisms. 

 The results of the bacteriological examination of the 

 pallial cavity of the oyster, and of the contents of the 

 rectum, showed that in the cases of those laid down in the 

 open water of the bay the colonies present were especially 

 small in number, whilst in those laid down in proximity 

 to the drain pipe the number was enormous {e.g., 17,000 

 as against 10 in the former case). It was found that 

 more organisms were present in the pallial cavity than in 

 the rectum. In the case of the oysters grown in water 

 infected with the Bacillus typhosus, it was found that 

 there was no apparent increase of the organisms, but that 

 they could still be identified in cultures taken from the 

 water of the pallial cavity and rectum fourteen days after 

 infection. 



It is found that the typhoid bacillus will not flourish in 

 clean sea water, and our experiments seem to show so 

 far that it decreases in numbers in its passage along the 

 alimentary canal of the oyster. It would seem possible, 

 therefore, that by methods similar to those employed in 

 the " Bassins de degorgement " of the French ostreicul- 

 turist, where the oysters are carefully subjected to a 

 natural process of cleaning, oysters previously contaminated 

 with sewage could be freed of pathogenic organisms or 

 their products without spoiling the oyster for the market. 



It need scarcely be pointed out that if it becomes 

 possible thus to cleanse infected or suspected oysters by 

 a simple mode of treatment which will render them 

 innocuous, a great boon will have been conferred upon 

 both the oyster trade and the oyster-consuming public. 



